Association of Red Cell Index and Hospital Mortality in Chronic Obstructive Pulmonary Disease Patients Admitted to the Intensive Care Unit: A Retrospective Cohort Study

Abstract

Purpose

This study aims to explore the association between red cell index (RCI) and hospital mortality in Chronic Obstructive Pulmonary Disease (COPD) patients in the intensive care unit.

Patients and Methods

This was a retrospective cohort research. The study included 821 COPD patients. Clinical data from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database was conducted. Multivariate logistic regression analysis was used to assess the correlation between RCI and in-hospital mortality. Age, SOFA score, diabetes mellitus, cerebrovascular disease, congestive heart failure and mechanical ventilation were considered for subgroup analysis.

Results

This study comprised 821 patients, of which 16.5% (124/821) suffered hospital mortality. In the multivariate logistic regression model, RCI was positively associated with hospital mortality, each unit increase in RCI was associated with a 3% increase in hospital mortality (odds ratio [OR] =1.03; 95% confidence interval [95CI%] =1.01–1.06). Meanwhile, compare with the lowest RCI group, the highest RCI groups tended to have higher risks of hospital mortality (OR [95% CI] 2.33 [1.27–4.27]). Additionally, subgroup analysis result was persistent among all the groups.

Conclusion

Higher RCI was positively associated with a higher risk of mortality in critically ill patients with COPD. Further investigation is necessary to confirm these findings.

Keywords:

• red cell index
• chronic obstructive pulmonary disease
• hospital mortality
• retrospective cohort study
• MIMIC-IV

Acknowledgments

Thanks to all the authors of this article. We are also thankful to J. Liu (People’s Liberation Army of China General Hospital, Beijing, China) for his help in revision.

Disclosure

The authors report no conflicts of interest in this work.